<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <link rel="stylesheet" href="./css/index.css" />
  <link rel="stylesheet" href="./css/inputnumber.css" />
  <title>购物车</title>
  <style>

  </style>
</head>

<body>
  <div class="app-container" id="app">
    <!-- 顶部banner -->
    <div class="banner-box"><img src="http://autumnfish.cn/static/fruit.jpg" alt="" /></div>
    <!-- 面包屑 -->
    <div class="breadcrumb">
      <span>🏠</span>
      /
      <span>购物车</span>
    </div>
    <!-- 购物车主体 -->
    <div class="main">
      <div class="table">
        <!-- 头部 -->
        <div class="thead">
          <div class="tr">
            <div class="th">选中</div>
            <div class="th th-pic">图片</div>
            <div class="th">单价</div>
            <div class="th num-th">个数</div>
            <div class="th">小计</div>
            <div class="th">操作</div>
          </div>
        </div>
        <!-- 身体 -->
        <div class="tbody">

          <!-- 渲染需要的行 -->
          <!-- 
            <div class="tr">
            <div class="td"><input type="checkbox" checked /></div>
            <div class="td"><img src="http://autumnfish.cn/static/火龙果.png" alt="" /></div>
            <div class="td">6</div>
            <div class="td">
              <div class="my-input-number">
                <button class="decrease"> - </button>
                <span class="my-input">2</span>
                <button class="increase"> + </button>
              </div>
            </div>
            <div class="td">12</div>
            <div class="td"><button class="del">删除</button></div>
          </div> 
        -->

        </div>
      </div>
      <!-- 底部 -->
      <div class="bottom">
        <!-- 全选 -->
        <label class="check-all">
          <input type="checkbox" />
          全选
        </label>
        <div class="right-box">
          <!-- 所有商品总价 -->
          <span class="price-box">总价&nbsp;&nbsp;:&nbsp;&nbsp;¥&nbsp;<span class="price">24</span></span>
          <!-- 结算按钮 -->
          <button class="button pay">结算( 6 )</button>
        </div>
      </div>
    </div>
    <!-- 空车 -->
    <div class="empty" style="display: none;">🛒空空如也</div>
  </div>
  <script>
    const dataArr = [
      {
        id: 1,
        icon: 'http://autumnfish.cn/static/火龙果.png',
        isChecked: true,
        num: 2,
        price: 6,
      },
      {
        id: 2,
        icon: 'http://autumnfish.cn/static/荔枝.png',
        isChecked: false,
        num: 7,
        price: 20,
      },
      {
        id: 3,
        icon: 'http://autumnfish.cn/static/榴莲.png',
        isChecked: false,
        num: 3,
        price: 40,
      },
      {
        id: 4,
        icon: 'http://autumnfish.cn/static/鸭梨.png',
        isChecked: true,
        num: 10,
        price: 3,
      },
      {
        id: 5,
        icon: 'http://autumnfish.cn/static/樱桃.png',
        isChecked: false,
        num: 20,
        price: 34,
      },
    ]
    let tbody = document.querySelector('.tbody')
    // 定义渲染函数
    function render(arr) {
      let res = arr.map(function (item) {
        return `
        <div class="tr" data-id="${item.id}">
              <div class="td"><input type="checkbox" ${item.isChecked ? 'checked' : ''} /></div>
              <div class="td"><img src="${item.icon}" alt="" /></div>
              <div class="td">${item.price}</div>
              <div class="td">
                <div class="my-input-number">
                  <button class="decrease"> - </button>
                  <span class="my-input">${item.num}</span>
                  <button data-id="${item.id}" class="increase"> + </button>
                </div>
              </div>
              <div class="td">${item.price * item.num}</div>
              <div class="td"><button data-id="${item.id}" class="button del">删除</button></div>
        </div>  
        `
      })
      // 将所有的tr盒子 拼接起来设置到 tbody中展示
      tbody.innerHTML = res.join('')

      // 结算
      let price = document.querySelector('.price')
      let pay = document.querySelector('.pay')

      let check = arr.filter(item => item.isChecked)
      let total = check.reduce((t, c) => t + c.num * c.price, 0)
      let num = check.reduce((t, c) => t + c.num, 0)

      // 设置 展示总价格和总数量
      price.innerHTML = total.toFixed(2)
      pay.innerHTML = `结算(${num})`

      // 当没有商品时，显示空空如也
      if (arr.length === 0) {
        document.querySelector('.empty').style.display = 'block'
      }
    }
    render(dataArr)

    //  加减功能
    tbody.addEventListener('click', function (e) {
      // 判断是否点击了减按钮
      if (e.target.className === 'decrease') {
        // 获取点击的自定义属性 id
        let id = e.target.parentNode.parentNode.parentNode.dataset.id
        // 找到数组中对应点击id 的id
        let index = dataArr.findIndex(item => item.id === +id)
        // 获取 数组中的num属性
        let num = dataArr[index].num
        num--
        // 让减到1 就就减不了
        dataArr[index].num = (num <= 0 ? 1 : num)
        // 重新渲染
        render(dataArr)
      } else if (e.target.classList.contains('increase')) {
        let id = e.target.dataset.id
        let index = dataArr.findIndex(item => item.id === +id)
        dataArr[index].num++
        render(dataArr)
      } else if (e.target.className === 'button del') {
        // 删除判断
        let id = e.target.dataset.id
        let index = dataArr.findIndex(item => item.id === +id)
        dataArr.splice(index, 1)
        render(dataArr)
      }
    })

    // 全选功能
    let checks = document.querySelectorAll('.tbody input[type=checkbox]')
    let checkAll = document.querySelector('.check-all input')
    checkAll.addEventListener('change', function () {
      // 让小选按钮的选中效果 跟着 全选按钮走
      dataArr.forEach(item => item.isChecked = this.checked)
      render(dataArr)
    })

    tbody.addEventListener('change', function (e) {
      if (e.target.tagName === 'INPUT') {
        // 获取点击的水果的id
        let id = e.target.parentNode.parentNode.dataset.id

        let index = dataArr.findIndex(item => item.id === +id)

        dataArr[index].isChecked = e.target.checked
        // 小选按钮都选中，全选按钮选中
        checkAll.checked = dataArr.every(item => item.isChecked)
        render(dataArr)
      }
    })
    // // 当选中所有的小选按钮的时候，全选按钮也要选中，只要有一个没有选中，全选按钮也不要选中
    // checks.forEach(item => {
    //   item.addEventListener('change', function () {
    //     // 将伪数组 转换为 真数组 在使用真数组every方法
    //     // const cks = Array.from(checks)
    //     // 使用every方法判断 小选按钮是否被全选
    //     // 让全选按钮的checked 跟着小选按钮every方法的返回值
    //     checkAll.checked = Array.from(checks).every(item => item.checked === true)
    //   })
    // })

  </script>
</body>

</html>